The present invention encompasses a means for providing anti-static and softening benefits to fabrics in an automatic dryer. More specifically, certain hygroscopic ethoxylated materials are employed to provide anti-static benefits on fabrics. The hygroscopic anti-static agents herein are conveniently formulated in combination with mixtures of monoglycerides, diglycerides, triglycerides and fatty alcohols which concurrently provide through-the-dryer fabric softening. The anti-static and mixed anti-static/softening compositions are preferably used in combination with a dispensing means adapted for use in an automatic dryer.
Treatment in an automatic clothes dryer has been shown to be an effective means for imparting desirable tactile properties to fabrics. For example, it is becoming common to soften fabrics in an automatic clothes dryer rather than during the rinse cycle of a laundering operation.
Fabric "softness" is an expression well-defined in the art and is usually understood to be that quality of the treated fabric whereby its handle or texture is smooth, pliable and fluffy to the touch. Various chemical compounds have long been known to possess the ability to soften fabrics during a laundering operation.
Fabric softness also connotes the absence of static "cling" in the fabrics, and the commonly used quaternary fabric softeners provide both softening and anti-static benefits when applied to fabrics. Indeed, with fabrics such as nylon and polyester, the user is more able to perceive and appreciate an anti-static benefit than a true softening benefit.
Cationic anti-static softening compounds and compositions designed for application to fabrics in an automatic dryer have been the subject of recent innovations. (See, for example, U.S. Pat. Nos. 3,632,396 and 3,686,025.) Other materials have been suggested for use as dryer-added fabric softeners; see, for example, U.S. Pat. No. 3,676,199 and the copending application of Murphy and Habermehl, Ser. No. 417,329, filed Nov. 19, 1973, now U.S. Pat. No. 4,000,340. Included among these prior softening compositions are various glycerides in combination with oil-soluble, lower-ethoxylated surfactants. Triglyceride fabric treating agents are disclosed in U.S. Pat. No. 3,785,973.
The common quaternary ammonium anti-static agents are not indicated for use in such compositions since the cationic quats and anionic surfactants undesirably interact. Since the glyceride softeners do not, themselves, possess substantial anti-static properties, it is desirable to provide compatible, non-cationic anti-static agents for use therewith.
It has now been discovered that certain highly ethoxylated, hygroscopic materials can be applied to fabrics to provide an anti-static effect thereto. The ethoxylates herein are highly water-soluble and are not particularly useful anti-static agents when employed in common fashion in an aqueous rinse bath, inasmuch as they are easily removed from fabrics by rinsing. Accordingly, such ethoxylates have not been widely recognized for use as anti-stats in laundering operations. It has now been found that such highly ethoxylated materials provide useful anti-static effects when applied to fabrics in a clothes dryer, since they are not removed from the fabrics by a subsequent rinsing step. Moreover, the ethoxylated anti-stats herein can be applied to fabrics in combination with glyceride mixtures particularly adapted for use as dryer-added fabric softeners.
The ethoxylated anti-stats herein are conveniently provided in combination with a dispensing means which releases a pre-determined, effective amount of the anti-stat onto fabrics in an automatic clothes dryer. Mixed glyceride fabric softeners can optionally be included with the dispensing means to concurrently soften the fabrics.
It is an object of the present invention to provide a means for imparting an anti-static benefit to fabrics in an automatic dryer.
Another object herein is to provide an article of manufacture adapted for use in an automatic dryer to impart anti-static and softness benefits to fabrics.
These and other objects are obtained herein as will be seen from the following disclosure.